Badio telegraphy amd telephony



J. H. HAMMOND, JR.

RADIO TELEGRAPHY AND TELEPHONY. APPLICATION FILED MAY 29, 1912. RENEWEDDEC. 28. 1916- 1,320,685, Patented Nov. 4, 1919.

WITNESSES I v INVENTOR %7v 301m HAYS mom), an, or enoucasrm,mssacnusnrrs.

name mnnenarm AND mmenom'.

. Application filed m 29, 1912, Serial No. 700,425.

To all whom it may concern:

Be it known that I. JOHN Hays HAM- MOND, J r., a citizen of the UnitedStates, residing at Gloucester, in the State of Massa chusetts, haveinvented certain new and useful Improvements in Radio Telegraphy andTelephony, of which the following is a specification. g

My invention relates to improvements in simultaneous radio telegraphyand telephony, and relates more particularly to systems in which: onegenerator of electric waves can be used and telephone conversations canbe carried on continuously," and telegraphic .messages sent at the sametime without. in-

terference.

In my system, a generator of contlnuous undamped electric waves -isused, these transmitter wave lengths, the other tuned 'to the othertransmittenwave length. One receiver circuit is arranged to receive onlythe telephone conversations; the other receiver circuit is arranged toreceive both telephone conversations and telegraph signals.

7 Referring to the drawlings,-

Figure 1 shows a transmitting station on mysystem.

Fig. 2 shows a receiving station on my system. 1 In Fig. 1, an are 0 issupplied from a source of direct current M N, and produces undampedoscillatory currents in the circuit- .0 C L, of a frequency determinedby the values of the inductance L and the capacity Antenna circuitA L TE is inductively coupled to L by coil L and the amplitude of theradiatedwaves is effected by the telephone transmitter T so as totransmit telephone conversation by means of the radiated waves. Thetelegraph key K I Specification of Letters Patent.

Patented Nov. 4,1919. Renewed December 28, 1916. Serial No. 139,419.

makes simultaneous contacts at G and H, and thus simultaneouslyshort-circuits parts of coils L and L so that only the parts J and J ofthe coils remain in circuit and so that the arc. oscillatory circuit andthe antenna circuit remain in tune, as they were before key K wasclosed. \Vhen key K is open, telephone conversations are carried on withradiated electric Waves of a specific length, and when K is closed,telephone conversations can still be carried on with waves of adifferent length, and at the same time telegraph signals, due to theclosing and opening of ,key K, can be transmitted. Fig. 2 shows one formof receiving system constructed in accordance with this invention andcomprising an open aerial cir-' cuit including an antenna B which leadsthrough two branch circuitsL C1'andL C to a ground E. This open circuitis tuned to respond to the two high" frequencies of the transmittingsystem. The branch circuits L and L C are coupled respectively to twoclosed resonant circuits L C and L C which are tuned to respond respectively to the two high frequencies of the transmittingsystem.Rectifier R supplies current from the circuit L C?" to one winding ofthe telephone receiver P Rectifier- R supplies current from'thecircuit LCto the telephone P through the inter.v

rupter I: and R also supplies current to the telephone winding P whichis onwhe same telephone recelver as P The circuits 0 C L and A L T E. ofthe transmitting station are in resonance with the circuit L C of thereceiving station, and when the transmitting key K is open, telephoneconversations only are transmitted and are received on one winding ofthe telephone I. The circuits 0 C J and A J T E of the transmittingstation are in resonance 'Wjith the circuit L C of the receivingstation, and Whenthe key K is closed. telephone conversations maycontinue to be transmltted-and will be received on the telephone windingP which is connected with transmitter. T, regardless of the position of.

' employed, and, in general, I do not confine myself to the specificmeans herein described for embodying my invention, but what I claimis: 1. In a system of simultaneous radio telegraphy and telephony, atransmitting station having closed and open oscillatory circuits,

means for changing the frequency of said circuits and maintaining saidcircuits in resonance with each other, means for trans-- mittingtelephone messages with all wave frequencies, and means for transmittingtelegraph signals at some wave frequencies, and a receiving station witha plurality of sets of open and closed receiving circuits, each set ofreceiving circuits being inresonance with one of the wave frequencies ofthe transmitting station. 3

2. In a system of simultaneous radio telegraphy and telephony, atransmitting station'having closed and open oscillatory circuits, meansfor changing-the frequency .of said circuits and maintaining saidcircuits in resonance with each other, means for transmitting telephonemessages continuously, and means for transmitting telegraph messagesintermittently.

.3. In system of simultaneous radio telegra'phy and telephony, atransmitting statlon having closed and open oscillatorycircuitsyinductances in said oscillatory circuits,

means for simultaneously changing the amount of sald inductances, meansfor transmitting telephone messages with all values of said inductances,and means for transmit? ting telegraph signals with some values of saidinductances. I

4. In an electric-wave transmission system, a transmitting stationhaving closed a and open oscillatory circuits, inductances in saidoscillatory circuits, means for simultane ously changing the value ofsaid inductances, and --concurrentl v sending telegraph signals, andmeans for. transmitting telephone messages with all values of "theinductances. r

5. A method of simultaneous radio telegraphy and telephony whichconsists in changing the wave frequency of, the transmitting circuitsand maintaining .them in resonance impressing telephone ,vibrations andtelegraph signals upon said circuits,

continuously emitting electric Waves and re ceiving-them uponseparatelystuned recelvmg clrcults.

6. A method of selective radio transmission, which consists incontinuously transmitting telephone messages and intermit tentlytransmittingtelegraph signals, changing'the wave length of theoscillatory circnits. of the transmitting station,.and mainhaving closedand open oscillatory circuits,

means for changing the frequenc of said circuits and maintaining saidcircuits in resonance with each other, means for transmittingtelephone-s messages continuously,

and means for transmitting telegraph mes: sages intermittently, and aI'QCBlVlllgStflt-lOll having means for receiving telephonemessages atall frequencies ofthe transmitting station. a

8. In a system of radio telegraphy and telephony, a source'of energy, aplurality-0f cooperating tuned devices arranged to be energized fromsald source, means fonvwrying the tuning of-said devices at will, ate-lephone transmitter adapted to continuously impress wavescorresponding to sound waves upon the waves of radiant energy emitted,and a telegraphing means intermittently op-.

erable for transmitting messages .-simul-taneously with the wavesimpressed bysaid transmitter. r x

9. In a system of radio telegraphy and telephony, a source of energy, aplurality of cooperating tuned devices arranged to be energized fromsaid source, means for varying the tuning of-said devices at will, atelephone transmitter adapted to continuously impress wavescorresponding to sound waves upon the waves of radiant energy emitted, atelegraphing means intermittently operable for transmitting messagessimultaneously with the wavesimpressed by said telephone transmitter,and separately tuned devices for receiving the respectivetelephone andtelegraph messages.

10. A radio system for simultanedusly transmitting telegraph andtelephone messages, oompr-ising-means for transmittinga seriesofperiodic radiant impulses having a predetermined frequency, meanincluding a telegraphindevice for changing the frequeue) of sai impulsesfrom time to time at the will of an operator to a second predeterminedfrequency'to form telegraph messages, and means for impressing upon saidimpulses of both frequencies variations.

a predetermined frequency, means including a telegraphing device forchanging the frequency of said impulses from time to time at the will ofan operator to a second predetermined frequency to form telegraphmessages, means for impressing upon said impulses of both frequenciesvariations corresponding to sound waves to transmit telephone messagessimultaneously with said telegraph'messages, and means for receivingsaid telegraph and telephone mes sages including two circuits tuned torespond to' said frequencies respectively, telephonic receiving meanscontrolled by both of said circuits fol-receiving said telephonemessages, and telephonic receiving means controlled by One only of saidcircuits for receivin said telegraph messages.

12. A ra io system for simultaneously transmitting telegraph andtelephone messages, comprising means for transmitting a series ofperiodic radiant impulses having a predetermined frequency, means including a telegraphing device for changing the frequency of said impulsesfrom time to time at the will of an operator to a second predeterminedfrequency to form telegraphic messages, means for impressing upon saidimpulses of both frequencies varie ations corresponding to sound wavesto transmit telephone messages simultaneously with said telegraphmessages, means for receiving said telegraph and telephone messagesincluding two circuits tuned to respond to said frequenciesrespectively, telephonic receiving means controlled by both of saidcircuits for receiving said telephone messages, telephonic receivingmeans controlled by one only of said circuits for receiving saidtelegraph messages, and means cooperating with said last-mentionedcircuit for impressing audible variations upon the impulses receivedthereby.

13. A radio system for simultaneously transmitting telegraph andtelephone messages, comprising an open aerial circuit,

means for causing said circuit to emit periodic radiant impulses havinga predetermined frequency, means including a telegraphic device forchanging the vfrequency of said impulses to a second predeterminedfrequency from time to time at the will of an operator to transmittelegraph messages,

r and means for impressing upon said impulses of both frequenciesvariations corresponding to sound waves to transmit telephonic messagessimultaneously with said telegraphic messages.

14.111 a radio system for simultaneously transmitting telegraph andtelephone messages, the combination with an open aerial circuitincluding an inductance, of means including an inductance cooperatingwith said first-mentioned inductance for causing said aerial circuit toemit aseries of periodic impulses having a predetermined frequency, ofmeans including a telegraphic device for simultaneously varying theeffective lengths of said inductances to change the frequency of saidimpulses toa second predetermined frequency from time to time totransmit telegraphic messages, and a .telephone transmitter arranged toimpress variations corresponding to sound waves upon the impulses ofboth of said frequencles to transmit telephone messages simultaneouslywith said telegraphic messages.

15. In a radio system for transmitting tele raphic and telephonicmessages, the com ination with means for emitting periodic radiantimpulses of a predetermined frequency, of means including a telegraphkey operative to change the frequency of said impulses from time to timeto a second frequency to transmit telegraphic messages,

and a telephone transmitter arranged to impress variations correspondingto sound waves upon the said impulses of both frequencies to transmittelephonic messages simultaneously with the said telegraphic messages.

16. A radio system for simultaneously V transmitting telegraphic andtelephonic messages, comprising means for transmitting periodic radiantimpulses having a predetermined frequency, of means including atelegraph key operable tochange the frequency of said impulses from timeto time ting telegraphic and telephonic messages,

comprising means for transmitting a series of perlodio impulses having apredetermined frequency, means including a telegraphic device forchanging the frequency of said impulses to a second predeterminedfrequency from time to time at the will of an operator to send atelegraphic'message, and means for impressing upon said impulses of bothfrequencies variations corresponding to sound wavesto send a telephonicmessage simultaneously with said telegraphic message.

18. A system for simultaneously transmitting telegraphic and telephonicmessages, comprising means for transmitting a'series of periodicimpulses having a predetermined frequency, means including a telegraphicdevice for changing the frequency of said impulses to a secondpredetermined frequency from time to time at the will of an operator tosend a telegraphic message, means for impressing upon said lmpulses ofboth frequencies variations corresponding to sound waves to sendatelephonic message simultanleouslly with said telegmphic message,

and means for simultaneously receiving saidtelegraphic and telephonicmessages including a receiving device responsive to said impulses ofboth of said frequencies for receiving said telephonic message, .andadevice responsive only tosaid impulses -of said second-mentionedfrequency for receiving said telegraphic message.

19.. A system for simultaneously transmitting telegraph and telephonemessages, comprising mcans fortr-ansmitting a series of periodicimpulses ha a predetermined 2-0. A system for simultaneouslytransmitting telegraph and telephone messages, comprising means fortransmitting a series of periodic impulses having a predeterminedfrequency, means including a telegraph key for changing the frequency ofsaid impulses from time to time to a second frequency to send atelegraphic message, a telephone transmitter arranged to modify saidimpulses ofbothjof saidfrequencies in accordance with sound Waves totransmit a telephone" message simultaneously with said telegraphicmessage, and means for simul:

I taneously receiving both of said messages ineluding a deviceresponsive alternately to said impulses of both of saidfrequencies and:a. device responsive only to said impulses of said'second-mentim-iedfrequency, said lastmentioned device including means for varying theeffect .of the received impulses of said second-mentioned frequency at arate within audibility. v

21. A method of simultaneous telegraphy and telephony, which consists ingenerating a series of'periodic impulses having a predeterminedfrequency, changing the frequency of said impulses from time to time atthe will 'of an operator to transmit a radio-tele-' graphic message, andimpressing upon said mpulses of all frequencies varlatlons correspendingto sound Waves. to transmit" a radio telephonic message simultaneouslywith said telegraphic message. I

22. A method of simultaneous telegraphy [and telephony,whichconsists ingenerating a series of periodic impulses having a predeterminedfrequency, changing the frequency of said impulses from time to time atthe will of an operator to transmit a radio-telegraphic message,impressing upon said lmpulses of all frequencies var ationscorresponding to sound-Waves to transmit a radio-telephonic messagesimultaneously with-said:- telegraphic message, and selectivelyreceiving said impulses of different:

frequencies causing a receiving device to respond to said impulsesofeach of said he quencies to receive said telephonic message,

and controlling-another receiving device as aresu'l-t'of the actionofsaid impulses of one of said frequencies.

23. A method of simultaneous radio-telegraphy and telephony, whichconsists in generatlngaseries-ofperiodic radiant impulses having a'predetermined frequency, changing the frequency of said impulses fromtimeto time at the will of'an operator to transmit a radio-telegraphicmessage, and impressing upon said impulses of allfrequencies'ivariations corresponding to sound waves t6 transmit aradio-filephonic message simultaneously with said telegraphic message.

24. A method of multaneous radio-teleg-. raphy and telephony, whichconsistsin gem crating a series of periodic radiant impulses having apredetermined frequency,-changing the frequency of said impulses fromtimeto' time at the will ofmn' iperator to transmit a radio-telegraphicmessage, impressing upon sa d impulses of all frequencies valuationscorresponding to sound'wa-ves to transmit a radio -tejlep'h-onic messagesimultaneously with said telegraphic message, and. selecfrequencicscausing a receivin device to-respond to said impulses of-eac of saidfrequencies to receive said telephonic message and controlling anotherreceiving device as 'a'result' of the action of said impulses of one ofsaid frequencies.

This specification signed and witnessed this 22nd day of May A, D.,191*2.

JOHN HAYS H oNn JR.

Witnesses:

MABELJ. Coornn, Omvr. B. KING.

tivel-y receiving said impulses of different

